Wife Was In A Car Accident, And Her Friend Who Was A Passenger Is Now Suing Her. Need Some Advice.

A little over a year ago my wife and her friend were in a car accident that totaled my wife’s car and put both of them in the hospital. The other vehicle sped through a red light and hit them dead on.

Her friend, who was in the passenger seat, is now suing her for injuries.

I’m wondering if this is normal, and what our options are. Any information or advice would be appreciated. Thanks.

EDIT - editing to share that the friend is suing my wife, the car that hit them, and the insurance companies.

UPDATE - Thanks everyone for the helpful information! I understand now that this is pretty common. We will let insurance handle it from here!